Frigits Deluxe(Think of It! $29.99 Score:) You'll want this on the fridge door! It's great fun to discover the many ways to arrange the magnetic shoots, wheels, and spinners so that the marbles drop into the catch box. 7 & up. SNAP INFO: Kids who might not be able to get down on the floor to make a marble run can do this in a wheelchair at the refrigerator door! It's great fun to discover the many ways to arrange the magnetic chutes, wheels, and spinners so that the marbles drop into the catch box. Marbles do fall off easily while the run is being constructed, so have a large supply of extra marbles on hand..

Expandagon Hoberman Kit(Hoberman Designs $40 Score:) You've probably seen Hoberman's spheres in science museums, but now kids can create flexible geometric shapes with simple connections. Sets have expandable squares that are key to making big structures. The manual could be a little more user friendly, but once you get started this is an addictive toy. PLATINUM AWARD '00. An Expandagon Actuator, a turntable display stand that motorizes creations looked promising but was not ready for testing. ($30). 8 & up.

Lego System Classic Building Sets(Lego Systems, Inc. $3.99 Score:) Lego, the granddaddy of plastic building blocks, is a must-have for this age group. Unlike the themed models in the line these open-ended sets with a mix of bricks, wheels, doors, and mini-figures allow kids to build and design their own creations. Also a great value, Lego Classic Play Desk ($19) comes with 225 pieces. 5–7.

B.C. Bones Wooden Prehistoric Animal Models (B.C. Bones $30 Score:) These sturdy Baltic-birch puzzles/models come in 22", 36", 42" & 96" variations. Our testers found some harder than others. In fact some needed glue to hold them in place. Nevertheless, kids were thrilled to display them with pride and because of their size they make handsome decorations once they are assembled. We recommend the Woolly Mammoth and Stegosaurus. These are truly parent-child projects that require strong hands, patience and following directions. 9 & up.

KNEX(KNEX $5 Score:) Testers continue to report that you need more finger strength with K'NEX than with Legos. That said, fans of K'NEX will enjoy the challenging Mission in Space sets with an International Space Station. We still love the solar powered construction sets which were Platinum Award winners.

Gearbotics(Learning Resources $58.95 Score:) This series of motorized plastic gears are interesting to construct. We still highly recommend the Robot, Oogly Googly, Sonic Insect, and Space Station (more than this year's Monster). The original nonmotorized Gears! Gears! Gears! sets remain our favorites because they are more open-ended and develop problem-solving skills as kids make their own moving machines. ($20/$40 ). New for 2003 , Under the Sea Set ($29.95 ) with 67 pieces including fish, turtles, whales, and an octopus. 6 & up.

Wooden Dinosaur Models(B.C. Bones $20 Score:) Kids who are wild about dinosaurs --will often spout off the dinosaur's long names and how big they grew--but how big is that compared to the living room-say or the block you live on? Kids can use a traditional yard stick, tape measures or they can count how many steps they need to take to measure 3 feet. Another choice is to measure off 10 feet of string. If the Allosaurus model they are building was 36 feet in real life --have them compare that to the house you live in…how many car length could that be? Other dinosaurs in books can be compared the same way. By the way, wooden dinosaur models (B.C. Bones $30 & up depending on size) requires working in a step by step way-translating directions from paper to real thing. Kids also need to use spatial relationships and a far amount of patience. New smaller kits with paint did not test well: "way too confusing, would be great with clearer directions." New architectural landmark kits looked stunning but were not ready for testing. 9 & up.

Block-N-Roll (Taurus Toys $19.99 Score:) A new twist on marble runs, this engrossing multipiece set (60 & 100) has blocks with grooves, drop-through slots, ramps, and turns that link together to make an endless variety of runways. New for 2001, they have added new twists with Loop-D-Loops ($4.95).

K'nex Screamin'Serpent Roller Coaster(KNEX $89.99 Score:) Our test family raved about the 1280 piece set that stands 6 feet by 3 feet when built! They said their child was so "thrilled with the results that it was a bigger hit than Disney World!" That said, they reported that it took over 36 hours to build and is truly for dedicated K'nex builders. The Trampoline (scored a four) was also a multiday project that our 10 year old builder thought was "neat" but only for those with lots of patience. The set also required some "jerryrigging" to get all the parts working smoothly.